1. Field of Invention
The present invention relates to a rim for a bicycle and, more particularly, to a composite rim.
2. Related Prior Art
Traditional rims for bicycles are made such as alloy. A metal rim is made of a metal strip. The metal strip is made into a circular shape by rolling. Two ends of the metal strip are joined together by soldering. Such a metal rim, however, is heavy. Furthermore, the process for making such a metal rim is complicated. Moreover, the point of soldering becomes a weak point from which fracture could easily occur. The life of such a metal is therefore reduced. In addition, with inherent ductility, such a metal rim could easily be deformed in a violent bump. Such deformation could jeopardize the safety of a rider.
A composite rim is found in U.S. Pat. No. 6,991,298 for example. The composite rim includes a body 12 made of fiber-reinforced plastic and a tire-receiving ring 14 made of metal. The body 12 is surrounded by the tire-receiving ring 14. The body 12 includes sidewalls 20 and 22 and a cross member 30 formed between the sidewalls 20 and 22. The body 12 is formed with a crown that includes crown sidewalls 37 and 39. The tire-receiving ring 14 includes braking members 51 and 53 and a base member 50 formed between the braking members 51 and 53. The crown sidewalls 37 and 39 of the body 12 is clamped by the braking members 51 and 53 of the tire-receiving ring 14. Beads 58 and 60 are formed on internal faces of the braking members 51 and 53. The beads 58 and 60 can be engaged with two compliant beads of a tire. External faces of the braking members 51 and 53 are used as braking faces 52 and 54 for contact with brake shoes. The braking faces 52 and 54 are however too smooth to cause sufficient friction against the brake shoes.
The present invention is therefore intended to obviate or at least alleviate the problems encountered in prior art.